title: Localization, distribution, and function of the calcium-sensing receptor in sperm.
abstract: The intracellular movement of calcium, through calcium channels, plays a  major role on sperm cell function. The calcium-sensing receptor (CaSR), a  molecular mechanism by which many cells detect changes in extracellular  calcium concentration, has not been described in spermatozoa. The aim of this  study was to investigate the expression of the CaSR in testicular tissue and  sperm cells and the functional consequences of spermatozoid CaSR activation by  calcimimetics. CaSR mRNA and protein were identified both in rat testicular  tissue and in rat spermatozoa using real-time reverse  transcription-polymerase chain reaction and immunohistochemistry,  respectively. Functionality of CaSR was evaluated by studying the influence of  calcimimetic AMG 641 on rat and pig sperm motility. Treatment with AMG 641 100  nM for 1 hour increased rat sperm motility from a score of 1.0 ± 0.1 to  3.8 ± 0.3 (P < .05). AMG 641 also resulted in a modest but  significant increase in the pig sperm motility parameters evaluated by  computer-assisted sperm analysis. AMG 641 was effective in a wide range of  concentrations but resulted in a more marked effect at 50-100 nM. In  addition, AMG 641 did not have any negative effect on sperm viability, which  was measured by flow cytometry. In conclusion, our results demonstrate the  expression of functional CaSR in testicular tissue and sperm, which can be  activated by calcimimetic AMG 641.
authors.affiliation: Dept Medicina y Cirugia Animal, Universidad de Cordoba, Campus Universitario Rabanales, Ctra. Madrid-Cadiz km 396, Cordoba, Spain. pv2megaf@uco.es
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Mendoza
authors.forename: Carlos C
authors.initials: CC
authors.lastname: Perez-Marin
authors.forename: Luis
authors.initials: L
authors.lastname: Garcia-Marin
authors.forename: Juan A
authors.initials: JA
authors.lastname: Madueño
authors.forename: Charles
authors.initials: C
authors.lastname: Henley
authors.forename: Escolastico
authors.initials: E
authors.lastname: Aguilera-Tejero
authors.forename: Mariano
authors.initials: M
authors.lastname: Rodriguez
mesh_terms: D000818:Animals; D001483:Base Sequence; D017931:DNA Primers; D006801:Humans; D008297:Male; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D060888:Real-Time Polymerase Chain Reaction; D044169:Receptors, Calcium-Sensing / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013081:Sperm Motility; D013094:Spermatozoa / Q000378:metabolism*; D013552:Swine
chemical_list: D017931:DNA Primers; D012333:RNA, Messenger; D044169:Receptors, Calcium-Sensing